Предмет: Геометрия, автор: obeme1228

Площадь полной поверхности тетраэдра равна 12, а объем – 4. Найдите радиус вписанной в него сферы.​

Ответы

Автор ответа: 3ztg4ycrtp
0
Для нахождения радиуса вписанной сферы в тетраэдре можно использовать следующие формулы:

Площадь поверхности тетраэдра (S) связана с его объемом (V) и радиусом вписанной сферы (r) следующим образом:

S = 4 * π * r^2

V = (1/3) * A_base * h

где A_base - площадь основания тетраэдра, а h - высота тетраэдра от его вершины до плоскости основания.

Мы знаем, что S = 12 и V = 4. Пересчитаем площадь основания A_base:

12 = 4 * π * r^2

Разделим обе стороны на 4 * π:

3 = r^2

Теперь извлекаем квадратный корень:

r = √3

Таким образом, радиус вписанной в тетраэдр сферы равен √3.
Наверное так.
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